mmap vs alloc

[Arnt Gulbrandsen]

Jakob Schlyter writes:
> I'd like to second this - do not rely on overcommit.
>
> is performance worse with mmap?

Performance should be the same, but there's a different problem: if you 
edit the file while nsd has it mapped, fun ensues.

I agree, though. It's better to mmap() and pray that the file isn't 
changed, than to read() and pray that overcommit won't explode.

--Arnt